Welded butt-strap connection for sheet metal



' Feb. s,` 1927.

Filed- Sept. 14, 1923 y Patentedl Feb. 8, 1927.

uNiTED'STATES PATENT OFFICE.'

ERNEST Homin', or ZURICH, sWIrznRLND. y

WELniszi) :BUTT-STRAP CONNECTION ron signer METAL.

' Application ledyeptemberli, 1923; Serial No. 662,792,1an-d in Germany September 28, 1922.'v

Known butt-strap connections' in which the sheet-metal partsare joined by a buttstrap'welded to them runningthe length of the" sheet-metal joint'to be .bridged over,

have thedisadvantagethat the strap covers' the joint. throughout itsfwhole extent, and so, `especial-1y when appliedon both sides,

' prevents' examination :of it, which in .man

I tages-areatvoided -In Aitv vthere are free; spaces `interinediatefbetween the connecting ca'ses, especially inv the-welded 'seams' of ho low-Ware subject to .internal 'or' externalv fpr ssnre, is indispensable, .l and lbutt-straps w tol such hollow ware' on 'one Iside' 'fllyloi welded seams give` rise to deleterious strapjeonnection by which these disadvanportions' which cover the joint vand are welded-toj the sheet-metal; and these free ,SPa'ceSleae the joint visible.' Examination sof S .l l c i.

--Itken atthe'jomt between the edgespf a L Shfl'` metal." plate oripl'ates',` showing one article.' y'

. `everal examples of construction yof the Y is `bject Aofthe invention are illustrated lin accompanying drawing in which; -i 1 'is a. longitudinal' sectionalnview form ofthe improved connection; j i

:F1g. .f2/ is a plan.l view ofthe connection throngh itlie .center line," of the reinforced joint show riin Fig'- 2;

ing; members; x

Fi 4 is,. avp lan view of a'lslieet inetal joint illustrating afmodited form of the connect- Fig; 5 is a lnviewillustrating a flur-A l ther inodifiedvfiorm' of connecting member;

i' Figs. 6 and 7 are respectively a plan yiew and a transversesectionalf view showing a *still'furtheiffinodiication of the connectingmembers; "'1

` 'ofxthe'fconnecti-ng members over` the joint;

necting means.

lsheet-metal.

l are views similar to Fig.- 2, butiishowing inodications of the dispositiontrating a further modification of theV con- The'same characters of reference designate the same parts in the dlerent 'figures of the drawings.

In the form shown in Figures 1 to 3, a and b are the pieces of sheet-metal to be joined.' Their abutting edges,A which may ibe bevelled to for/m a V as shown, o'r X in cross-section', or left parallel, are joined by a welded seam o. To strengthen this weldedseam butt-strap segments al are arranged in staggered 'j' relation` above .and -below theI seam c 'sothat on each side there are free spaces'intermediate between the butt-Strap segments. The .edges of the buttstrap segments d; which also may be bevelled, or straight-'as shown', are welded tothe solid In this way the seam c is visible throughou@ alternately on' one side land the other in ysp'itewiof the presence of the butt-strap segments d. Bending strains 'cannot arise in the seam 'c because the buttj strap segments yare arranged: symmetrically above and below the centre of gravityof` the cross section of the sheet-metal (see Figure 3), .which lies in the seam Ac.' The whole joint is stiffer than one havin parallel-edged butt-strap welded upon vone side (e. g` above), or even on both sides v an ordinary' (above and below)7 because-each separate blittlstrap segmentcl nis welded around its edge nearly up to,`or evenright across the joint seam c. Springingor yielding of such a butt-strap segment therefore does. not occur as it doesnn ordinary butt-straps with -Wel'ded edges parallel to the joint.

- '('In consequence' ot theseY advantages the strength ot' a seam reinforced with such alternate butt-strap segments d is equal to or greater than that of' the solid plate.

-Soine orallof the butt-strap segments d may loe-wholly orfpartlyfwelded on before v the joint is weld-ed at '0., ley-which means strainsin the sheet-metal upon welding at thehseain le, which might bring-'about warpingjof the'joint, may be'avoided or diminished.

The' forni oftheV buttstrap segments d maybe Varied 'as desired. VhilefFigure 2 shows vcircular butt-strap segments, those of. `the examples in Figures 4- and 5 are quadrilateral, in thecase of IFigure 4 themidline', and in Figure 5 a diagonal, lying in the direction of the joint c.

In'the exampleof Figures 6 and 7 the butt-strap segments where they bridge the seam are corrugated in case the seam stands.

up from the sheetmetal.

r The drawings show the butt-strap curved in cross-section to it the curvedslieets 4to be joined; it may obviously be fiat for flat sheets, or angular where the seam is on an angle, and so on.

The free space intermediate between the butt-strap segmentsA need not be equal in s length to the segments in the direction`of the seam, so that the projections of neigln bouring butt-strap segments in plan contact with each other; it may be smaller (Figure 8) or larger (Figure 9).

Figures l() and 11 illustrate an example of construction in which a longitudinal buttstrap j' is provided on one side which has portions g cut away through which the seam is visible. The butt-strap is wel-ded to the sheet metal along its outer edges, and if desired around the edges of the holesI also.,

There may be another butt-strap of ordinary kind or perforated similarly t'o f onthe otherside of the joint; and in--the latter case the holes g on the two staggered.

Vhat I claim and desire to secure by Letsides are relatively ters Patent is:-

1. A connection for sheet metal joints,

comprising connecting means having Apor-l 1,617,1iak

tions welded to the sheet metal at opposite sides of the joint, said welded vportions being spaced apart to expose said joint.

2. A butt-strap connection lfor sheetmetal,`form.ed of separate buttgstr-ap segments which bridge over the sheet metal joint at intervals and are welded to the sheet-metal while the joint remains visibley between them. ,i

3. A butt-strap connection for sheet- `metal'formed of separate4 butt-strap segments which bridge over the sheet-n1etal of, said welded portions 'being'spacedapartv to expose the joint, and connecting elements i having vportions welded to the metal 'at the opposite side thereof, said welded portions being spaced apart, the welded' portions at i one side-.Lof the -v-metal being disposed in staggered relation to those at the opposite side thereof.

In .testimony whereof I. have signed my name to this specification.

ERNEST HoEHN. 

